What is the ideal / best / normal operating temperature?

Hello!

I have a 2000 Jeep Grand Cherokee Limited, 4.7L V8. I just bought it last week and I've noticed that when the Jeep reaches "it's normal operating temperature," the temperature gauge needle is just below the 215 mark. I've looked in the owner's manual and can't find anything in there, and the closest I've been able to find on the internet gives me a range of 160 to 195. I know if I went to a parts store, I could probably have 3-4 choices on temperature for a thermostat. What is the best? With cars I've owned, I always try to go in the 160 - 180 range, but I've heard that some cars are intended to run at a little higher temps.
Can anyone help steer me in the right direction?

Thanks!

The best temperature for it to run at is the temperature it was designed to run at.
Do not change the thermostat from OEM temperature, (195 degree if I recall) a lower temperature t stat might let it run cooler but it may adversely affect emission controls and performance.

The normal operating temperature is 210 - 215 degrees so you are in the ball park. The temperature sending units can vary slightly also, as long as it's staying below 220* it should be fine.

That is VERY helpful; thank you! I wonder why they have the engines run so warm.

I wonder why they have the engines run so warm.
Mostly for emission purposes.

Emissions. What torques me is the fact that these gas hogging, oil burning, Ozone disolving diesels get away with murder when it comes to emissions.

Well as long as the engine was intended to run that warm, we're good.